Very little is known about Apple's plans for the next 12-inch MacBook, but the company will presumably make the leap to Intel's Skylake platform. Skylake-based PCs will not only be faster but support things like magnetic resonance charging, allowing compatible gadgets to be charged at distances further than those supported by standard inductive wireless chargers, which essentially demand direct contact. Another option will be quick peripheral connections via WiGig, automatically pairing compatible devices once they enter a set range.
It's not clear how many Skylake technologies Apple will adopt. The first Skylake chips could ship as soon as August, but since Apple only released the first 12-inch MacBook this year, the company's next upgrade window is likely sometime in 2016.
Another upgrade could be support for Thunderbolt 3. The format will actually incorporate USB-C and USB 3.1 — enabling Apple to stick with a single port — but permit speeds between 20 and 40 gigabits per second depending on the connected cable.